AXPZ20 KNHC 261613 CCA
Corrected to add mention of gale warning for low pressure near
Tropical Weather Discussion
NWS National Hurricane Center Miami FL
1525 UTC Fri Aug 26 2016
Tropical Weather Discussion for the eastern Pacific Ocean from
the Equator to 32N, east of 140W. The following information is
based on satellite imagery, weather observations, radar, and
Based on 1500 UTC surface analysis and satellite imagery through
Tropical Storm Lester is centered near 17.1N 115.0W at 26/1500
UTC or about 435 nm to the south-southwest of the southern tip of
Baja California. Lester is moving west or 280 deg at 6 kt with
maximum sustained winds of 50 kt with gusts to 60 kt. The
estimated minimum central pressure remains 1000 mb. Satellite
imagery shows numerous strong convection within 120 nm in the
northern semicircle of the center, impacting Clarion Island.
Scattered moderate isolated strong convection is noted elsewhere
from 16N to 19N between 110W and 118W, impacting Socorro Island.
Lester is forecast to continue moving away from the Mexican
offshore waters on Friday, and strengthen to a hurricane near
17N120W late Friday. Please read the NHC forecast/advisory under
AWIPS/WMO headers MIATCMEP3/WTPZ23 KNHC or the public bulletin
under MIATCPEP3/ WTPZ33 KNHC for more details.
Showers and thunderstorms continue to show signs of organization in
association with a broad area of low pressure located near
13.5N133W or about 1340 miles east-southeast of the Big Island of
Hawaii. Numerous moderate to scattered strong convection is noted
mainly west of the center from 11N to 16N between 135W and 137W.
Scattered moderate convection is from 12N to 13N between 134W and
136W. Another circulation was becoming evident overnight, and this
may becoming the dominant circulation according to latest
satellite imagery, and the low position may have to be relocated
farther south accordingly. Winds are likely 25 to 30 kt with 6 to
9 ft seas. The system will intensify later today as it becomes
more organized, and a gale warning is in effect. There is a high
chance of tropical cyclone development within the next 48 hours as
the low pressure moves westward or west-northwest at 15 to 20 kt,
moving west of area by Saturday night.
No tropical waves at this time.
...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...
The monsoon trough axis extends from 12N95W to 09N100W to
11N110W. It resumes at 14N126W to low pressure near 13.5N133W
1008 mb to beyond 11N140W. Scattered moderate isolated strong
convection is noted within 240 nm north of the monsoon trough axis
between 95W and 105W, and within 150 nm south of the axis between
100W and 110W.
OFFSHORE WATERS WITHIN 250 NM OF MEXICO...
An ASCAT pass from several hours ago indicated moderate southerly
flow over the northern Gulf of California between 1004 mb low
pressure centered over the lower Colorado River basin and high
pressure farther west. These winds may be increasing slightly
this morning as the surface ridge off Baja California builds.
Limited fetch will keep the resultant seas generally 2 to 4 ft.
Moderate northerly flow will persist off the Pacific coast of the
Baja California peninsula with 5 to 6 ft seas. T.S. Lester is
impacting Clarion Island and surrounding waters currently, but
will move west of the area through late Friday. Little change is
OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND
WITHIN 750 NM OF ECUADOR...
Scattered moderate convection is noted within 120 of the Central
American coast this morning, with strong convection noted off
Guatemala. This convection will weaken through this afternoon, but
will likely emerge again tonight. Light to moderate southwest winds
south of the monsoon trough will continue to spread to the coastal
sections through Friday, then a light and variable onshore flow is
expected Saturday and Sunday.
A broad surface ridge covers the remainder of the area,
extending from a large 1040 mb high near 47N146W. The pressure
gradient between the low pressure located near 13.5N133W and the
ridge will yield fresh winds across the trade wind belt, generally
from 21N southward to near the trough. Seas ranging from 6 to 8
feet presently in this area.